Method for manufacturing and golf club head

ABSTRACT

A method for forming a golf club head comprises placing an uncured composite material between a core and a mold that comprises a first piece and a second piece. The second piece is moved towards the first piece such that the uncured composite material is compressed between the core and at least a portion of the mold. The uncured composite material is heated. A first portion of the golf club head is removed from the mold. A second portion of the golf club head is provided. The first portion is attached to the second portion. In certain arrangements, the second portion is formed from a metallic material.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/253,005, filed Oct. 16, 2008, now U.S. Pat. No. 7,704,164 which is acontinuation of U.S. patent application Ser. No. 11/401,472, filed Apr.10, 2006, now abandoned which is a continuation of U.S. patentapplication Ser. No. 10/941,474, filed Sep. 15, 2004, now U.S. Pat. No.7,041,005, issued May 9, 2006, which is a continuation of U.S. patentapplication Ser. No. 10/621,641, filed Jul. 17, 2003, now U.S. Pat. No.6,872,152, issued Mar. 29, 2005, which is a continuation of U.S. patentapplication Ser. No. 09/878, 634, filed Jun. 11, 2001, now U.S. Pat. No.6,623,378, issued Sep. 23, 2003, which are hereby incorporated byreferenced herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an improved method for producing a golfclub head, and more particularly to an improved method of producing aclub head made of a carbon fiber composite.

2. Description of the Related Art

A wood-type golf club typically includes a hollow shaft with a club headattached to the lower end of the shaft. The club head typically includesa load-bearing outer shell with an integral or attached strike plate.The strike plate defines a substantially planar front surface or strikeface for striking a golf ball.

A recent trend in the industry is to make the club head out of strong,yet lightweight material, such as, for example, titanium, a titaniumalloy or a carbon fiber composite. Of these materials, carbon fibercomposites are particularly interesting to golf club designers becauseit has a density that is roughly one third of the density of titaniumbut is almost as strong as titanium. Accordingly, carbon fibercomposites are particularly suitable for very large club heads (i.e.,club heads that define an internal volume greater than 400 centimeterscubed).

Despite their low density and strength, club heads that are madeentirely of carbon fiber composites are generally not popular. This isdue, in part, to the relatively high stiffness that is typical of carbonfiber composites. Such stiffness usually is undesirable especially inthe strike plate. Moreover, carbon fiber composites are not particularlydurable. Thus, composite club heads have a tendency to wear out in theareas that are subjected large amounts of wear and friction (e.g., thesole of the club head).

To overcome some of these problems, it has been suggested that the clubhead be made from a combination of titanium or alloy and carbon fibercomposites. Specifically, it has been suggested that a club head can beformed from an outer shell made of a carbon fiber composite, which isattached to a strike plate made of a titanium or a titanium alloy.However, existing methods for manufacturing such a club have not beensatisfactory. For example, one golf club manufacturer attempted toco-cure a metal strike plate with a composite outer shell. Morespecifically, a metal strike plate was placed in a mold along with aninflatable bladder that was surrounded by a uncured composite material.To cure the composite, the bladder was inflated to press the uncuredmaterial against the mold and the strike plate. However, fitting thestrike face into mold and removing the bladder from the cured club headwas difficult and time consuming.

SUMMARY OF THE INVENTION

An aspect of the present invention is an improved method for producing aclub head comprising of a metal strike plate and a composite shell. Afurther aspect of the present invention is the realization that such aclub can be produced by attaching the metal strike plate to thecomposite shell after the composite shell is formed. However, for themetal strike plate to be successfully attached to the strike plate thecomposite shell must be produced in a manner that ensures fighttolerances and smooth surfaces on both the inside surfaces and outsidesurfaces of the shell.

Accordingly, one aspect of the invention is a method for forming a golfclub head. The method comprises placing an uncured composite materialbetween a core and a mold that comprises a first piece and a secondpiece. The second piece is moved towards the first piece such that theuncured composite material is compressed between the core and at least aportion of the mold. The uncured composite material is heated. A firstportion of the golf club head is removed from the mold. A second portionof the golf club head is provided. The first portion is attached to thesecond portion.

Another aspect of the invention is a method for forming a golf clubhead. The method comprises placing an uncured composite material betweena core and a mold that comprises a first piece and a second piece. Thesecond piece is moved towards the first piece such that the uncuredcomposite material is compressed between the core and at least a portionof the mold. The uncured composite material is heated. A first matingsection is formed on the first portion. A first portion of the golf clubhead is removed from the mold. A second portion of the golf club head isprovided. The first portion is attached to the second portion.

Yet another aspect of the invention is a golf club head comprising ashell made of a composite material that is attached to a strike platethat is formed of a metallic material. The shell includes a first matingsection and the strike plate including a second mating sectionconfigured to mate with the first mating section.

Still yet another aspect of the present invention is a golf club headcomprising a shell made of a composite material that is attached to astrike/sole plate combination. The strike/sole plate combinationincludes strike plate and sole plate, which are integrally formed andmade of a metallic material. The shell includes a first mating sectionand the strike/sole plate combination includes a second mating sectionconfigured to mate with the first mating section.

For purposes of summarizing the invention and the advantages achievedover the prior art, certain objects and advantages of the invention havebeen described herein above. Of course, it is to be understood that notnecessarily all such objects or advantages may be achieved in accordancewith any particular embodiment of the invention. Thus, for example,those skilled in the art will recognize that the invention may beembodied or carried out in a manner that achieves or optimizes oneadvantage or group of advantages as taught herein without necessarilyachieving other objects or advantages as may be taught or suggestedherein.

All of these embodiments are intended to be within the scope of theinvention herein disclosed. These and other embodiments of the presentinvention will become readily apparent to those skilled in the art fromthe following detailed description of the preferred embodiments havingreference to the attached figures, the invention not being limited toany particular preferred embodiment(s) disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the invention will now be described withreference to the drawings of a preferred embodiment, which are intendedto illustrate and not to limit the invention, and in which:

FIG. 1 is a front perspective view of a golf club head having certainfeatures and advantages according to the present invention;

FIG. 2 is a rear perspective of the golf club head of FIG. 1;

FIG. 3A is a cross-sectional view of the golf club head of FIG. 1;

FIG. 3B is an enlarged cross-sectional view of the area with the circlelabeled 3B of FIG. 3A;

FIG. 3C is a cross-sectional view of a modified arrangement of a golfclub head;

FIG. 4 is a side perspective view of a strike/sole plate combination andouter shell of the club head of FIG. 1;

FIG. 5 is a top view of the strike/sole plate combination of FIG. 4;

FIG. 6 is a cross-sectional view of a mold according to a method in theprior art;

FIG. 7 is cross-sectional view of a mold according to another method inthe prior art;

FIG. 8 is a perspective view of a mold for a golf club head havingcertain features and advantages according to the present invention;

FIG. 9A is a front view of a core of the mold of FIG. 8;

FIG. 9B is a right side view of the core;

FIG. 9C is a left side view of the core;

FIG. 9D is a top view of the core;

FIG. 9E is a bottom view of the core;

FIG. 10 is a cross-sectional view of the mold of FIG. 8;

FIG. 11A is a top view of a first mold piece of the mold of FIG. 8;

FIG. 11B is a front view of the first mold piece;

FIG. 12A is front view of a second mold piece of the mold of FIG. 8; and

FIG. 12B is a bottom view of the second mold piece.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1-5 illustrated a club bead 10 having certain features andadvantages according to the present invention. With initial reference toFIG. 1, the club head 10 comprises a strike plate 12. The strike plate12 defines a substantially planar front surface or strike face 14 forimpacting a golf ball. A hosel 16 extends upward from the strike plate12. The hosel 16 is configured to be coupled to a golf club shaft (notshown) in a well known manner. The strike plate 12 is preferably made ofa strong, yet lightweight metal, such as, for example, titanium or atitanium alloy.

The club head 10 also comprises an outer shell 20 that is preferablymade of a strong yet lightweight composite material, such as, forexample, a carbon fiber reinforced epoxy or carbon fiber reinforcedpolymer. As best seen in FIG. 3A, the outer shell 20 includes an innersurface 21, which defines an interior volume 22 of the club head 10, andan outer surface 23. The club head 10 also includes a toe region 24 anda heel region 26, as is well known. The bottom of the club head 10 isdelimited in part by a sole 28 and the top of the club head is delimitedby a crown 30.

With particular reference to FIGS. 2 and 4, the illustrated club head 10also comprises a sole plate 32, which extends along the center of thesole 28 from the strike plate 12 to the rear of the club head 10. Asbest seen in FIG. 4, in the illustrated arrangement, the sole plate 32is formed integrally with the strike plate 12. That is, the sole plate32 and the strike plate 12 form a single strike/sole plate combination34. The outer shell 20 preferably is attached to this sole/strike platecombination 34, as will be described in more detail below. The soleplate 32 protects the 28 sole of the club head 10 from friction and wearduring a golf swing. Accordingly, the sole plate 32 preferably is madeof a material that is more durable than the shell 20, such as, forexample, a metal. More preferably, the sole plate 32 is made of the samestrong, yet lightweight metal as the mice plate 12. It should beappreciated, however, that several features and advantages of thepresent invention can be achieved in an arrangement wherein the strikeplate 12 and the sole plate 32 are not integrally formed (i.e., thestrike plate 12 and the sole plate 32 are separate pieces). Moreover, insome arrangements of the present invention, the club head 10 can beformed without the sole plate 32. In other arrangements, the club head10 can be formed without the strike plate 12. However, the illustratedarrangement is preferred because the mechanical properties of metal areparticularly suited for the strike plate 12 and the sole plate 32. Asmentioned above, the strike plate 12 and the sole plate 32 arepreferably made of a strong, yet light weight metal, such as, forexample, titanium. In such an arrangement, the strike plate 12 and/orthe sole plate 32 can be formed by casting, forging, rolling or acombination of casting, forging and/or rolling.

FIG. 3C illustrates another arrangement of the club head 10. In thisarrangement, the club head 10 includes an inner shell 35 that ispreferably integrally formed with the strike/sole plate combination 34.In this arrangement, the inner shell 35 defines the inner surface 21 ofthe club head 35. The inner shell 35 is preferably made of the samestrong, yet lightweight metal as the strike/sole plate combination. Theouter surface 23 of the club head 10 is defined by the outer shell 20,which surrounds the inner shell 35 and is preferably made of a strongyet lightweight composite material, such as, for example, a carbon fiberreinforced epoxy or carbon fiber reinforced polymer.

As mentioned above, the outer shell 20 preferably is attached to thestrike/sole plate combination 34. To improve the strength of theconnection between the outer shell 20 and the strike/sole platecombination 34, the outer shell 20 and the strike/sole plate combination34 preferably include an interlocking joint 36, which is best seen inFIGS. 3A and 3B. In the illustrated embodiment, the joint 36 comprisesmating sections 38 a, 38 b formed on the outer shell 20 and thestrike/sole plate combination 34 respectively. Each mating section 38 a,38 b preferably includes an abutment surface 39 a, 39 b that istransverse to the outer surface 23. More preferably, the abutmentsurface 39 a, 39 b, lies substantially normal to the outer surface 23.The abutment 39 a, 39 b surfaces help to align the shell 20 with thestrike/sole plate combination 34 and to prevent lateral movement ofthese two components 20, 24 with respect to each other. Each matingsection 38 a, 38 b, preferably also includes an attachment surface 41 a,41 b. The attachment surfaces 41 a, 41 b are at least two (2) times, andpreferably, four (4) times as wide as the thickness t of the outer shell20. The attachment surfaces 41 a, 41 b preferably provide a surface foran adhesive as will be explained in more detail below. The attachmentsurfaces 41 a, 41 b preferably are generally parallel to the outersurface 23 of the shell 20 and midway between the inner surface 21 andouter surface 23 of the outer shell 20. This arrangement is preferredbecause it permits a longer attachment surface and thicker matingsections 38 a, 38 b, which increases the strength of the joint 36 andthe bond between the shell 20 and the strike/sole plate combination 34respectively. In the arrangement illustrated in FIG. 3C, the attachmentsurfaces 41 a, 41 b can extend along the entire length of the outershell 20.

As best seen in FIG. 4, the mating sections 38 a, 38 b, preferablyextend completely along the interface between the outer shell 20 and thestrike/sole plate 34 combination. However, it should be appreciatedthat, in a modified arrangement, the mating sections 38 a, 38 b couldextend only partially along the interface between the outer shell 20 andthe strike/sole plate combination 34. In the illustrated arrangement,each piece 38 a, 38 b includes two abutment surfaces 39 a, 39 b, whichare separated by the attachment surfaces 41 a, 41 b. That is, theabutment surfaces 39 a, 39 b, and the attachment surfaces 41 a, 41 b,form an interlocking steps. However, it should be appreciated that themating sections 38 a, 38 b can be formed into a variety of other shapesgiving due consideration to the preference of providing a secureconnection between the outer shell 20 and the strike/sole platecombination 34. For example, the mating sections 38 a, 38 b can comprisean interlocking tongue and groove arrangement or a matching inclinedsurface arrangement, each of which includes abutment surfaces 39 a, 39 band attachment surfaces 41 a, 41 b.

To permanently secure the outer shell 20 to the strike/sole platecombination 34, an adhesive, such as, for example, an epoxy is appliedto one or both of the mating sections 38 a, 38 b, preferably, along theattachment surfaces 41 a, 41 b. In a modified arrangement, the outershell 20 can be secured to the strike/sole plate combination 34 byfasteners that can extend through the joint 36. As best seen in FIGS. 3Aand 5, the sole plate 32 preferably includes an annular rib 40, whichextends from the periphery of the sole plate 32 and into the cavity 22of the club head 10. The annular rib 40 advantageously increases therigidity of the sole plate 32. Of course, those of skill in the art willrecognize that the sole plate 32 can be formed without the annular rib40.

To ensure a secure bond between the outer shell 20 and the strike/soleplate combination 34, the joint 36 (i.e., the interlocking step surfaces38 a, 38 b) preferably are made with tight tolerances and smoothsurfaces. More preferably, these components are made with a tolerancethat is less than approximately ±0.15 millimeters. With respect to theinterlocking step surface 38 a of the outer shell 20, prior methods forproducing carbon fiber club heads are not adequate for creating thedesired tight tolerances and smooth surfaces. This is especially truewith respect to the inner surface 21 of the outer shell 20 and theportion of which forms the interlocking step surface 38 a of the outershell 20 (see FIG. 3B).

For example, FIG. 6 shows a cross-section of a carbon fiber club headbeing produced according to the methods of the prior art. According tothis technique, an uncured composite material 50 is wrapped around aninflatable bladder 52. The bladder 52 and the composite material 50 areplaced within a mold 54 and heated to a specified temperature to softenthe uncured composite. The bladder 52 then is inflated with pressurizedair, steam or oil through one or more openings 56. As the bladder 52expands, the composite material 50 is pressed against the inner surfaces55 of the mold 54. After the composite material 50 cures, the golf clubhead is removed from the mold 54 and the bladder 52 is deflated andremoved from the golf club through the one or more openings 56.

One problem with the above-described method is that it is difficult toobtain tight tolerances and smooth surfaces on the interior surfaces 58of the club head. This difficulty is due primarily to the nature of theinflatable bladder 52. As the bladder 52 expands, the composite material50 is pressed against the hard smooth inner surface 55 of the mold 54.This tends to produce a smooth surface on the outer surfaces 60 of thecomposite material. In contrast, the relatively flexible surface of theinflatable bladder 52 presses against the interior surfaces 58 of thecomposite material. This tends to produce an uneven surface, which makesit difficult to obtain the tight tolerances and smooth surfaces.

A technique that is likely to be more successful in obtaining tighttolerance on the interior surfaces of the club head is shown in FIG. 7.This method uses, sheets 60 of fibrous material that are wrapped arounda core 62 made of a low melting point alloy. The core 62 and the fibrousmaterial 60 are placed within a cavity of a splittable mold 64 made of apair of mold halves 66, 68. The fibrous material 60 lies within aperipheral gap is formed between the core 62 and the mold 68. Once thecore 62 and fibrous material 60 are in place, resin is injected into theperipheral gap through an opening 70. The resin flows through thefibrous material and hardens to form the golf club head. The mold 68 isheated to melt the core 62, which can be removed from a hole 72 formedin the club head.

This method, however, has a number of significant drawbacks. Forexample, because the resin must flow through the fibrous material, thefiber loading of the fibrous material must be kept to a relatively smallamount. This reduces the strength of the final composite material. Themethod also requires the two halves 66, 68 of the mold 64 to be sealedso as to prevent the resin from leaking out of the mold 64. Thisincreases the cost of manufacturing.

To address the above-noted problems, Applicant has invented a method formanufacturing a golf club having certain features and advantages. Themethod utilizes a mold 98, which is shown in FIG. 8. The mold includes acore or mandrel 100, which is shown in detail in FIG. 9A-E. The corepreferably is made of a hard material, such as, for example, aluminum orsteel. Preferably, the core 100 comprises a first piece 102 a and asecond piece 102 b. However, it should be appreciated that the core 100can comprise a single piece or more than two pieces. The two piececonstruction is preferred for reasons that will be set forth below. Thecore 100 defines an exterior surface 104, which corresponds generally tothe desired shape of the interior surface 21 of the outer shell 20. Inparticular, the exterior surface 104 includes a ridge 106 that forms ananalog to the interlocking step surface 38 a of the club head 10 (seeFIG. 4). Of course, if the joint 36 has a different configuration theexterior surface 104 can be modified accordingly.

The mold 98 also comprises a first mold piece 112, which is shown inFIGS. 8 and 10-11B. The first mold piece 112 includes an inner surface114, which generally corresponds to the desired shape of a portion ofthe outer shell's 20 exterior surface 23. More specifically, in theillustrated arrangement, the inner surface 114 of the mold correspondsto a lower portion (i.e., the portion of outer shell 20 that liesgenerally below the crown 30) of shell's 20 exterior surface 23. Theillustrated first mold piece 112 also includes a spacing groove 116. Thegroove 116 is configured to receive a tongue piece 118 that is formed onthe core 100 (see FIGS. 9A, 9B, and 10). The tongue 118 and groove 116cooperate to properly align the core 100 within the cavity 110. Whilethe tongue 118 and groove 116 are preferred for the simplicity andreliability, those skilled in the art will recognize that there areother ways to ensure the proper alignment of the core 100 within thecavity 110.

The mold 98 further includes a second mold piece 120, which is shown inFIGS. 8, 10, 13 and 14. The second mold piece 120 has a second innersurface 122, which preferably is configured to generally correspond tothe desired shape of the crown 30. The top portion 120 is furtherconfigured such that it can be moved towards or away from the first moldpiece 112. Accordingly, as shown in FIG. 8, the top portion 112 isconnected to the bottom portion 110 by a plurality of shafts 124, whichare threaded. The shafts 124 preferably extend through threaded holesformed in the second mold piece 122 and threaded holes formed in thefirst mold piece 112. Thus, the second mold piece 120 can be movedtowards the first mold piece 112 by rotating the shafts 120. Of course,those skilled in the art will recognize that there are other ways formoving the first and second mold pieces 112, 122 towards each other.

As shown in FIGS. 8 and 10, the mold 98 preferably also includes a thirdmold piece 130. The third mold piece 130 includes a third inner surface132, which is configured to contact a portion 134 of the exteriorsurface 104 of the core 100.

To form the outer shell 20 of the club bead 10, an uncured compositematerial 150 is placed (i.e., laying up) around the core 100 (see FIG.10). The uncured composite material 150 preferably is a carbon fiberreinforced thermoset resin or a carbon fiber reinforced plastic resin.The composite material 150 and the core 100 preferably are then placedwithin the first mold piece 112. Once the core 100 is in place, thethird mold piece 130 is attached, preferably with bolts (not shown), tothe first mold piece 112. In this position, the third mold piece 130securely holds the core 100 and composite material 150 within the firstmold piece 112.

The second mold piece 130 then is moved towards the first mold piece112. Accordingly, the uncured composite material 150 is compressedbetween the first, second mold pieces 112, 120 and the core 100. As thesecond mold piece 120 is moved towards the first mold piece 112, thelower surface 152 (see FIG. 10) of the second mold piece 120 eventuallycontacts the upper surface 154 of the first mold piece 112, resulting ina positive stop. Preferably, the first and second mold pieces 112, 120are configured such that when the lower and uppers surfaces 152, 154contact a uniform gap exists between the second piece 120 and the core100. In this manner, the composite material 150 is uniformly compressedbetween the first and second mold pieces 112, 120 and the core 100.

Preferably, while the composite material 150 is being compressed, themold 98 is being heated in an oven to a temperature between 200-500degrees Fahrenheit. More preferably, the mold 98 is heated to atemperature of approximately 350 degree Fahrenheit for approximately 10minutes. The compressing and heating cures the composite material 150into the desired shape, which is determined by the shape of the core 100and the inner surfaces 114, 122 of the first and second mold pieces 112,120.

After the composite material 150 is cured, the second and third moldpieces are removed. The core 100 can then be removed form the curedshell 20. The illustrated two piece construction of the core 100 aidesthe removal of the core 100. The finished shell 200 is removed from themold 98 and attached to a corresponding strike/sole plate 34 combinationwith epoxy as described above.

In the illustrated arrangement, the strike/sole plate combination 34 ismade of titanium or a titanium alloy. This arrangement is preferredbecause the material properties of titanium are particularly suited forthe strike plate 12 and the sole plate 32. However, it should beappreciated that, in a modified arrangement, the above-described methodcan also be utilized for a club head wherein the strike plate 12 and/orthe sole plate 32 are made of a composite material. In such anarrangement, a second mold (not shown) can be formed utilizing theprinciples described above. The second mold can be used to create astrike plate, a sole plate, or a strike/sole plate combination made of acomposite material.

In another modified arrangement, the core 100 is attached to orintegrally formed with the first mold piece 112. In such an arrangement,the uncured composite material 150 is placed over the core 100. Thesecond mold piece 130 then is moved towards the first mold piece 112.After the composite material cures, the composite material 150 can beremoved from the first mold piece 112.

Although this invention has been disclosed in the context of certainpreferred embodiments and examples, it will be understood by thoseskilled in the art that the present invention extends beyond thespecifically disclosed embodiments to other alternative embodimentsand/or uses of the invention and obvious modifications and equivalentsthereof. In addition, while a number of variations of the invention havebeen shown and described in detail, other modifications, which arewithin the scope of this invention, will be readily apparent to those ofskill in the art based upon this disclosure. It is also contemplatedthat various combination or subcombinations of the specific features andaspects of the embodiments may be made and still fall within the scopeof the invention. Accordingly, it should be understood that variousfeatures and aspects of the disclosed embodiments can be combine with orsubstituted for one another in order to form varying modes of thedisclosed invention. Thus, it is intended that the scope of the presentinvention herein disclosed should not be limited by the particulardisclosed embodiments described above, but should be determined only bya fair reading of the claims that follow.

What is claimed is:
 1. A golf club head comprising: a shell made of acomposite material that is attached to a strike plate that is formed ofa metallic material, the shell including a first mating section and thestrike plate including a second mating section configured to mate withthe first mating section; wherein the strike plate includes a faceportion, a sole plate portion coupled to the face portion, and a crownportion coupled to the face portion, the face portion and the sole plateportion and the crown portion comprising titanium; wherein the crownportion has an outwardly facing attachment surface generally between anouter surface and an inner surface of the crown portion and a firstabutment surface extending between the attachment surface and the outersurface of the crown portion, wherein the attachment surface defines acrown opening; wherein the shell comprises carbon fiber reinforced epoxyand is coupled to the attachment surface, the shell having an outersurface, an inner surface, and a second abutment surface extendingbetween the outer and inner facing surfaces of the shell; and whereinthe attachment surface is bonded to the inner surface of the shell, thefirst abutment surface is connected to the second abutment surface, andthe attachment surface is at least four times as wide as a thickness ofthe shell.
 2. The golf club head of claim 1, wherein the first matingsection and the second mating section extend entirely along an interfacebetween the shell and the strike plate.
 3. The golf club head of claim1, wherein the first mating section includes a first abutment surface,which is transverse to an outer surface of the shell and the secondmating section includes a second abutment surface, which issubstantially parallel to the first abutment surface.
 4. The golf clubhead of claim 1, wherein the first mating section includes a firstattachment surface, which is generally parallel to an outer surface ofthe shell and the second mating section includes a second attachmentsurface, which is substantially parallel to the first attachmentsurface.
 5. The golf club head of claim 1, wherein the first matingsection includes a first abutment surface, which is transverse to anouter surface of the shell and a first attachment surface, which isgenerally parallel to an outer surface of the first portion and thesecond mating section includes a second abutment surface that issubstantially parallel to the first abutment surface and a secondattachment surface that is substantially parallel to the firstattachment surface.
 6. The golf club head of claim 1, wherein adhesivesecures the first mating section to the second mating section.
 7. Thegolf club head of claim 1, wherein adhesive secures the first matingsection to the second mating section.
 8. The golf club head of claim 1,wherein the first mating section overlaps and is external to the secondmating section.
 9. The golf club head of claim 1, wherein the sole plateportion includes a rib that protrudes inwardly from a periphery of thesole plate portion into an interior of the golf club head.